Apron mount and control for carry-type scrapers



D. E. MURRAY 2,529,848

APRON MOUNT AND CONTROL FOR CARRY-TYPE SCRAPERS Nov. 14, 1950 2 Sheets-Sheet 1 Filed April 4, 1947 ATTORNEYS 7 Nov. 14, 1950 D. E. MURRAY Q 2,529,848

APRON MOUNT CONTROL FOR CARRY-TYPE SCRAPERS Filed April 4,1947 2 Sheets=$heet 2 o F/g. 2 2d mvsNT'oR .DanaldE'. Murray ATTORNEYS 34 Patented Nov. 14, 1950 APRON MOUN T AND CONTROL FOR CARRY-TYPE SCRAPERS Donald E. Murray, Modesto, Calif.

Application April 4, 1947, Serial No. 739,439

Claims.

This invention relates in general to improve-- ments in carry-type earth moving scrapers.

In particular the invention is directed to, and it is an object to provide, a novel mount and control arrangement for the vertically adjustable front apron which the scraper includes in cooperative relation to the open front end of the bowl.

Another object of the invention is to provide an apron mount and control, as above, which is operative to cause the apron to swing relatively sharply rearwardly with a, scooping motion as said apron approaches its lowered or closed position, thus giving a very effective final loading action. Conversely, when the apron begins its opening motion, it shifts relatively sharply forwardly with the initial lift so that the apron is considerably ahead and above the digging blade as is desirable to free an unobstructed loading of the bowl.

A further object of this invention is to accomplish the foregoing scooping action by hinging the side arms of the apron, intermediate their ends, for vertical articulating motion; there being stops positioned to limit downward motion of the rearmcst arm sections to a predetermined position, and pull means are applied to the front arm sections to then forcefully swing the same downwardly causing the apron to scoop rearwardly at the lower end portion of its path of travel.

A further object of the invention is to produce a practical device and one which will be exceedingly effective for the purpose for which it is designed.

These objects are accomplished by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claims.

In the drawings:

Fig. 1 is a side elevation of a scraper embodying the present invention showing the apron in its closed position.

Fig. 2 is a similar view but shows the apron in its open position.

Fig. 3 is a plan View of the scraper embodying the invention.

Referring now more particularly to the characters of reference on the drawings, the invention is embodied in a scraper which includes an earth carrying bowl open at its forward end and supported within a frame, indicated generally at 2.

The frame is supported, at its rear end, by a pair of transversely spaced rear wheel trucks 3. The forward end of the frame 2 is vertically adjustably supported by a draft yoke 4 pivoted at its rear ends, as at 5, to attachment arms 6 which project from opposite sides of the bowl; the draft yoke 1 including a gooseneck 1 which couples to a front wheel truck 8. 7

Vertical adjustment of the frame-mounted bowl, at its forward end, is accomplished by a 2 a fluid pressure actuated power cylinder 9 con nected between the gooseneck I and the upper end of a rigid transverse arch i0 fixed in connection with the frame 2 at the forward end of the bowl I. The arch I0 is stabilized by a longitudinal stay beam I I which extends from the top of such arch at a, downward and rearward incline to connection with the frame 2 at its rear end.

Within the bowl I the scraper is fitted with a normally retracted endgate i2 pivoted, as at l3, for upward and forward swinging movement to discharge a load from the scraper; there being a transverse cutting and digging blade M at the forward edge of the bottom of the bowl.

A front apron, indicated at I5, is disposed in cooperative relation to the open front end of the bowl l and is vertically adjustably mounted in the manner hereinafter described in detail. The endgate i2 and front apron H: are adapted to be advanced and elevated from their retracted and closed positions, respectively, by means of the following arrangement:

A double-acting, fluid pressure actuated power cylinder IE is mounted lengthwise on the stay beam 5 i, with the piston rod l1 projecting rearwardly, and carrying a sheave block IS on its rear end. Control cables !9 and 20, included in a single length of cable which turns about the sheave block 18, extend over direction-changing sheaves 2i and 22, and thence lead to, and connect in operative relation with, the endgate I2 and front apron l5, respectively.

The piston rod I? is normally retracted, but

upon advance thereof by the cylinder IE, it will.

be seen that a pull is exerted on the cables l9 and 2i: to actuate said endgate l2 and apron 5 in the manner described in copending application, Serial No. 672,823, filed May 28, 1946.

The front apron I5 is fitted, at opposite ends and adjacent the top, with rearwardly projecting side arms, indicated generally at 23, pivotally connected at their rear ends, as at 22, to the bowl frame 2 adjacent the top thereof and some distance rearwardly of the vertical plane of the transverse cutting and digging blade M.

Each of the side arms 23 comprises a rear section 25 and a front section 26, which sections are hinged together at adjacent ends, as at 21, for vertical buckling or articulation in the manner shown in Fig. 1.

On each side of the scraper it is fitted with a pair of vertically spaced stops 28v and 29; the

stops 28 engaging the rear sections 25 of the When the front apron I5 is lowered towardrits closed position, as when the bowl I is substantially full after aloading: operation, thesections,

25 and 26 of the side arms 23 remain in alinement until the rear sections 25 abut the stops 28. Thereafter, with further lowering of the front apron I5, the front sections 26 swing downwardly and rearwardl about the hinges 21 as aXes, which imparts to the apron I a relatively sharp, rearward scooping motion until such apron engages the transverse blade Hi. 'This scooping motion affords a very efficient final loading action, particularly with respect to the over-burden of earth which tends to push ahead of the blade I4 during the final loading stages. With such scooping action the apron I5 carries much of such overburden into the bowl I, substantially increasing the final load.

The above described scooping motion of the front apron I5 is power actuated, at the proper moment, and from the cylinder I6, in the following manner:

- The sheave block I8 is fitted, on opposite sides,

with elongated sleeves 3B which extend, at a forward and upward incline, alongside the power cylinder I6, and run, in guided relation, on fixed guide rods 3!. The sleeves 3!! thus travel with the piston rod I1 and sheave block I8. Adjacent their upper ends the elongated sleeves 30 are fixed to pull cables 32 which extend rearwardly, and thence pass about direction-changing sheaves 33, which ultimately direct such cables for forward extension alongside the bowl I to connection, at anchor points 3 3, with rigid depending legs 35 on corresponding front sections 26 of the apron side arms 23.

With the above arrangement, it will be seen that with extension or projection of the piston rod H, to lift the front apron I5 and advance the endgate I2, the pull cables 32 then hang slack. I-Iowever, when the piston rod I? and sheave block i8 are retracted to permit of retraction of the endgate I2 and lowering of the front apron I5, the pull cables 32 are tensioned and come into action as said apron aproaches its closed position; thus effectivel and forcefully drawing the front apron rearwardly through its scooping path, as made possible by the described articulation of the apron side arms 23. There is thus a powered closing of the front apron in its scooping path. The relatively sharp rearward scooping motion of the front apron, as described, is accomplished by reason of the fact that the hinges 2'! are disposed generally in vertical alinement above the cutting and digging blade it.

Also, by reason of the described mounting of the apron, the latter shifts forwardly relatively sharp as it starts its path of opening motion; the apron thusbeing considerably ahead of, and above, the digging blade, even though said apron is partially open, as the digging operation begins. The digging operation is, of course, regulated by vertical adjustment of the bowl I and blade I4 by the power cylinder 9.

When the apron I5 is lifted, the front sections 26 initially swing upward until they close in abutting relation to the rear sections 25, whence both sections, remaining in such alinement, continue the upward motion until the sections 26 engage the stops 29.

From the foregoing description it will be read- 1137 seen that there has been produced such a device as substantially fulfills the objects of the invention as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure 4 from the'spirit of the invention, as defined by the appended claims.

Having-thus described the invention, the following is claimed as new and useful and upon which Letters Patent is desired:

1. In a scraper which includes a bowl having a forwardly movable endgate and a vertically adjustable apron, a power cylinder mounted lengthwise on top of the bowl, said cylinder including a projecting piston rod, guided cables leading from the piston rod operative to advance the endgate and lift the apron upon motion of said rod in one direction, the apron being mounted for a relatively sharp rearward scooping action as it approaches closed position, and a guided pull cable system leading from the piston rod and connected to the apron to urge the same rearwardly upon motion of said rod in a direction opposite to the direction which advances the endgate and lifts the apron.

2. A scraper, as in claim 1, in which the piston rod projects rearward, extension of said rod advancing the endgate and lifting the apron, and retraction of the rod urging the cable system in said opposite direction to cause said scooping action of the apron.

3. A scraper, a in claim 1, in which the piston rod projects rearward, extension of said rod advancing the endgate and lifting the apron, and retraction of the rod urging the cable system in said opposite direction to cause said scooping action of the apron; said cable system including pull cables running forwardly along opposite sides of the power cylinder from rearwardly thereof, corresponding sleeves attached to the piston rod and likewise extending along opposite" sides of the cylinder, the sleeves running on fixed guide rods, and'means connecting corresponding pull cables to the sleeves adjacent the forward ends of the latter.

4. An apron mount and control for a carry type scraper which includes a frame carrying a main bowl and an independently vertically adjustable front apron; such mount comprising a pair of transversely spaced arms pivoted to the sides of the frame and projecting forwardly of the pivot points, each arm including two sections pivoted together, means to prevent the sections hinging relative to each other 'in an upward direction but allowing the foremost sections to hinge downwardly relative to the rear sections, means on the frame to limit the downward movement of the rear sections, means on the frame operable to selectively lift the arms vertically and to allow the foremost sections to hinge downwardly, a cable connected to the apron below the said hinge point between the sections, and a power means on the frame connected with said cable and effective to pull the apron toward the front end of the mainbowl in any position of said main bowl.

5. A mount as in claim 4 in which the power means is a fluid pressure actuated power cylinder connected in operative relation to the cable.

DONALD E. MIURRAY.

REFERENCES CITED 7 The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,172,672 Daniels Sept. 13, 1939 2,301,158 Daniels Nov. 3, 1942 

